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Our purpose was to determine the influence of posture and breathing route on electromyographic (EMG) activities of nasal dilator (NDM) and genioglossus (GG) muscles during exercise. Nasal and oral airflow rates and EMG activities of the NDM and GG were recorded in 10 subjects at rest and during upright and supine incremental cycling exercise to exhaustion. EMG activities immediately before and after the switch from nasal to oronasal breathing were also determined for those subjects who demonstrated a clear switch point (n = 7). NDM and GG EMG activities were significantly correlated with increases in nasal, oral, and total ventilatory rates during exercise, and these relationships were not altered by posture. In both upright and supine exercise, NDM activity rose more sharply as a function of nasal inspired ventilation compared with total or oral inspired ventilation (P < 0.01), but GG activity showed no significant breathing-route dependence. Peak NDM integrated EMG activity decreased (P = 0.008), and peak GG integrated EMG activity increased (P = 0.032) coincident with the switch from nasal to oronasal breathing. In conclusion, 1) neural drive to NDM and GG increases as a function of exercise intensity, but the increase is unaltered by posture; 2) NDM activity is breathing-route dependent in steady-state exercise, but GG activity is not; and 3) drive to both muscles changes significantly at the switch point, but the change in GG activity is more variable and is often transient. This suggests that factors other than the breathing route dominate drive to the GG soon after the initial changes in the configuration of the oronasal airway are made.
The present research demonstrates that the extent to which people appreciate the influence past visceral states have had on behavior (e.g., the influence hunger has had on food choice) depends largely on their current visceral state. Specifically, we found that when people were in a hot state (e.g., fatigued), they attributed behavior primarily to visceral influences, whereas when people were in a cold state (e.g., nonfatigued), they underestimated the influence of visceral drives and instead attributed behavior primarily to other, nonvisceral factors. This hot-cold empathy gap was observed when people made attributions about the past behavior of another person or themselves, and proved difficult to overcome, as participants could not correct for the biasing influence of their current visceral state when instructed to do so. These different attribution patterns also had consequences for people's satisfaction with their performance. Those who attributed their poor performance to visceral factors were more satisfied than those who made dispositional attributions.
OBJECTIVES: To study driving behaviors after major lower-extremity amputations and to determine which factors influence return to driving after amputation. DESIGN: A cross-sectional study. SETTING: Data were collected from patients attending an outpatient amputee and prosthetics clinic between February 2001 and September 2001. PARTICIPANTS: A convenience sample (N=123). Inclusion criteria were: age greater than 18 years, unilateral or bilateral major lower-extremity amputation, minimum 1 year since prosthetic fitting, and active automobile driver within 6 months prior to amputation. Subjects had an average age of 63.4+/-12.1 years and were on average 6.8+/-8.3 years since amputation. Common causes for amputation were peripheral vascular disease (73.2%), trauma (13.8%), and tumor (12.2%). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Driving habits after lower-extremity amputation. RESULTS: Overall, 80.5% of participants were able to return to driving an average of 3.8 months after amputation, although the majority reported a decreased driving frequency. Female sex (odds ratio [OR]=.08; 95% confidence interval [CI], .02-.34), age of 60 years or greater (OR=.16; 95% CI, .03-.74), right-sided amputation (OR=.13; 95% CI, .03-.52), and preamputation driving frequency of less than every day (OR=.18; 95% CI, .05-.69) were all significantly related to a reduced likelihood of return to driving postamputation. Items that did not have a statistically significant association with return to driving included level of amputation, reason for amputation, preamputation automobile transmission, and accessibility to public transit. Subjects with left-sided amputation had significantly fewer concerns about driving, while those with a right amputation frequently required vehicle modifications (40.6%) or switch to a left-foot driving style for braking (81.3%) and accelerating (65.6%). Common barriers to return to driving included preference not to drive, fear and/or lack of confidence, and related medical conditions. CONCLUSIONS: The majority of subjects with major lower-extremity amputation were able to return to driving after major lower-extremity amputation. Major automobile modifications are commonly performed by right-sided amputees. Several predictors of return to driving and barriers preventing return to driving were identified.
Several distinct bodies of literature indicate that economic factors influence alcohol consumption and driving behavior, including: econometric studies of effects of income and price on drinking, studies of booming and depressed communities, studies of the effects of recession on mental health and studies of the effects of the business cycle on driving patterns. The core research questions of this study were: (1) Does the state of the economy affect the rate of fatal motor vehicle crashes involving drinking drivers? and (2) Is the relationship between the state of the economy and motor vehicle fatalities mediated by effects of economic conditions on amount of alcohol consumed and amount of driving? Data were collected on multiple indicators of economic conditions, alcohol consumption, vehicle miles traveled and rates per population of fatal crashes in the United States on a monthly basis from 1976 through 1985. Nonlinear time-series modeling methods were used to estimate both direct and indirect effects and both coincident and lagged relationships. Results showed that economic conditions significantly influence fatal crash rates both directly and via changes in aggregate amount of alcohol consumed and aggregate amount of driving. However, these interrelationships at multiple lags are complex and not yet fully understood.
In this paper, I have presented the assumption that some symptom pictures such as attachment to pain, the masochistic character, the negative therapeutic reaction, a basic depressive response, and anhedonia are rooted in a prevalence of organismic distress during the symbiotic phase. Neuroscientists taught us that early experiences are associated with the neuronal structuring of the developing brain, which then affects concurrent or subsequent reactions. In particular I followed Ginsburg's (1982) assumption of a neuronally, genetically given aggressive drive potential which influences and is influenced by early experiences, and which can interact with other gene potentials. In some patients aggressive drive components contributed to a less than harmonious basic core associated with failure of the early infant/mother interaction. Unpleasure prevailed during the symbiotic phase; aggressive energies predominated and enmeshed with the neuronal encoding, the early structuralization in both the neurophysiological and psychological meaning. Thus, the structuring of the function of internalization and the emerging self-object experience were disturbed from early on. This then continued to foster a proclivity for unstable (fusion and) diminished neutralization tendencies. As biological discharge phenomena evolve into vague psychological awareness, such an infant does not attain a sense of well-being, but rather attains a sense of "not-well-being" (Joffe and Sandler, 1965) which remains continuous or can be triggered--kindled--by any reactivating constellation, and the object is experienced as a source of unpleasure. This is in line with Mahler's bad mother and bad self-introjects. Primary narcissism has not evolved well or, said differently, is invested more with aggressive than with libidinal cathexis and is in an unfortunate association or balance with primary masochism. Aggressive drive components subsequently color fantasies, readiness for and severity of conflicts. The aggressivization of self-feelings and of the function of internalization with its influence on--and exacerbation of--the rapprochement crisis is traced into later symptomatology. The basic pathology as described in this paper then compounds the oedipally derived problems.
The aim of this study was to investigate driving under the influence of alcohol (DUI) risk profiles and predictors in a sample of pre-driving Brazilian youth, in the context of Brazil's new Traffic Code. Data were obtained in the Traffic Department in São Paulo from a sample of 2166 individuals. Subjects displayed a low level of knowledge about the laws and few believed the penalties would actually be enforced for those engaging in DUI. Findings suggest that changes in DUI laws in Brazil and elsewhere should be accompanied by enforcement and education in order to enhance levels of knowledge and credibility of the sanctions.
An enforcement emphasis project, "Operation Trucker Check," was established in order to determine the extent to which commercial tractor-trailer drivers were operating their vehicles while impaired by drugs. A total of 1079 drivers and their vehicles were assessed for driver and equipment violations, and drivers additionally underwent preliminary field sobriety tests conducted by drug recognition expert (DRE) officers. Anonymous urine specimens for drug analysis were requested, and 822 urine specimens were obtained in total. Compliance with the drug-testing portion was voluntary, and there was a 19% refusal rate. Overall, 21% of the urine specimens tested positive for either illicit, prescription, and/or over-the-counter drugs, and 7% tested positive for more than one drug. Excluding caffeine and nicotine, the largest number of positive findings (9.5%) were for CNS stimulants, such as methamphetamine, amphetamine, phentermine, ephedrine/pseudoephedrine, and cocaine. The second most frequently encountered drug class were the cannabinoids, with 4.3% of drivers testing positive for marijuana metabolites. Only 11 drivers (1.3%) were positive for alcohol. Sixteen truck drivers (1.6%) were charged with driving under the influence of drugs after a full DRE evaluation was conducted. The results indicate that in spite of comprehensive drug testing in the trucking industry, some tractor-trailer drivers are continuing to take illicit and other drugs with the potential of having a negative effect on their driving ability. On the other hand, only a few drivers were, in fact, deemed to be under the influence of drugs at the time of driving when evaluated by DRE officers.
Considerable interest has lately been expressed in motor car driving whilst under the influence of drugs. Unlike depressant drugs (e.g. alcohol) dance drugs are often perceived to enhance driving skills. The physical effects and the current lack of police roadside testing are possible contributing reasons for dance drug driving. This paper aims to show through a literature review on the subject, the demographics of those involved in dance drug driving and the extent to which certain dance drugs are implicated in drug driving incidents. Drug driving is found to be highest amongst the 18-35 year age group and more prevalent amongst adult males. Prevalence figures for driving under the influence of individual drugs are also given. The numbers of people involved in accidents/fatalities and testing positive for amphetamine, cocaine and other dance drugs is small. Although self-reporting especially of illegal activities is difficult to accurately evaluate, most of the reported studies use actual blood/urine samples and so can be considered accurate. The literature does not highlight any real concerns regarding dance drug driving in terms of prevalence although it does highlight the paucity of research in this area, in particular 'Culture E and driving'.
The testing of saliva or oral fluid at the roadside could be a powerful tool to detect drivers under the influence of drugs and has several advantages over urine screening. In 177 cases of individuals suspected of driving under the influence of drugs, oral fluid was collected at the roadside and analyzed in parallel to serum samples. The study was performed to investigate the variability of oral fluid analysis results in relation to blood/serum. In 45% of the cases single-drug use was found, and in 50% poly-drug use was found. Cannabis was most prevalent (78%), and 70% of these individuals were also positive for tetrahydrocannabinol in serum. Overall, 97% of oral fluid samples positive for any substance were also positive in serum. Comparing data of oral fluid and serum for amphetamine, MDMA, morphine, benzoylecgonine, and tetrahydrocannabinol, the sensitivities were 100%, 97%, 87%, 87%, and 92%, respectively. Overall specificity and accuracy were in the range of 91-98%. Discrepancies between a negative oral fluid sample and a positive serum sample could be explained by analytical insensitivity in the lower volume of oral fluid analyzed (estimated for 0.1 mL confirmation vs. 1 mL of serum) or a shorter detection window in oral fluid. The low prevalence of discrepancies with positive oral fluid and negative serum results (2-9% of the cases) may be explained by persistent oral contamination especially for orally consumed drugs, like MDMA and cannabis. It is concluded that the detection of a psychoactive substance in oral fluid taken at the roadside is highly predictive for the detection of the corresponding drug or its metabolite in serum. Oral fluid testing is therefore suitable for the efficient confirmation of drug use of drivers suspected of being under the influence of drugs.
OBJECTIVE: Prior research has shown that designated drivers (DD) are widely used as a preventive measure for driving under the influence. Despite the prevalence of alcohol involvement in boating accidents, much less is known about the use of a designated boat operator (DBO). The current study investigated the prevalence of DBO use in recreational boating and compared the characteristics of DD users and DBO users. METHOD: Several survey questionnaires were distributed to a group of undergraduate students at a large southwestern university for the purpose of investigating demographic characteristics, alcohol-use pattern, and other alcohol-related problem behaviors, such as driving and boating under the influence. RESULTS: Approximately 45% of the boaters reported they had drunk alcohol while boating, and approximately 70% had used a DBO in the most recent boating event. The DBO users were found to be similar to the DD users in terms of drinking pattern, age of drinking onset, and driving behaviors. CONCLUSIONS: High rates of alcohol use in recreational boating suggest the need for prevention strategies. Furthermore, future studies are needed to investigate the selection process of the DBOs and the differences between passengers and boat operators, which could shed light on strategies to prevent alcohol- involved boating injuries.
Each driver is influenced by the collective behavior of other drivers. At the same time, each driver is also part of this collective, and thus influences others. Underlying many driver control and traffic safety programs are two implicit and related assumptions: that drivers are sensitive to the "culture of driving" around them and emulate it; and, that a small shift in the behavior of few might be amplified or snowball to a much larger effect resulting in a changed traffic environment or a modified culture of driving. The paper discusses possible mechanisms for the interactions between individuals, collectives, and culture, drawing on literature from social psychology, sociology, economics, communication, epidemiology, and other disciplines. Traffic behavior modeling could benefit from considering concepts developed in other social disciplines while providing challenging research issues and data sources for testing and developing those concepts.
In newborn pigs (4-6 days old), recordings of efferent whole hypoglossal and phrenic nerve discharges were obtained during hyperoxia (or normoxia) and during hypoxia, before and after bilateral vagotomy. With intact vagi, spontaneous hypoglossal inspiratory activity was not observed and was not elicited by either spontaneous changes of electroencephalogram (EEG) or hypoxic stimulation (15% O2 in N2). After bilateral vagotomy, some animals had episodes of spontaneous hypoglossal inspiratory activity; power spectral analysis of EEG demonstrated that this inspiratory activity appeared synchronously with shifts of major peaks in EEG spectra from the delta band (0.5-3.5 Hz) to the theta band (3.5-7.0 Hz). Hypoglossal inspiratory discharges were also elicited by hypoxic stimulation and usually had a decrementing discharge pattern; in some cases, this activity had an augmenting discharge pattern. Our results suggest that hypoglossal motoneurons are poorly modulated by central inspiratory drive, requiring additional facilitatory influences, i.e. corticobulbar, intra-bulbar, chemical drive, before such modulation is observed.
We have studied the propensity for periodic breathing to occur in cats anaesthetized with pentobarbitone breathing either spontaneously or with the aid of a 'servo-respirator' governed continuously by the efferent phrenic nerve activity. Sustained periodic breathing could be induced increasing 'controller gain', either by increasing the gain of the respirator, or by lung deflation, which reflexly increased controller responses to both hypoxia and hypercapnia. Periodic breathing was potentiated both by hypoxia and by diminishing the central (CO2, H+)-drive by focal cooling at the ventral surface of the medulla, two procedures which increase the relative influence of hypoxic drive. Less hypoxia was needed to produce periodic breathing at high rather than low controller gains. Reducing controller gain to zero by constant artificial respiration always abolished periodic breathing. Periodic breathing was also eradicated when the relative importance of CO2 drive was enhanced by breathing the cats with CO2-enriched gas mixtures or with 100% O2. The results are consistent with theoretical predictions for the occurrence of oscillations in the mechanisms for the chemical control of breathing and indicate that increasing controller gas can produce periodic breathing. The results further emphasize the importance of the (CO2, H+)-drive in preserving ventilatory stability.
The adverse effects of minor tranquilizers, and more specifically benzodiazepines, on psychomotor and cognitive performance have been documented repeatedly over the years, and epidemiological studies have provided sufficient evidence of their role in traffic accidents. These studies indicate that drug plasma level (DPL) is insufficiently correlated with impairment and that other factors need to be considered in determining the impairment vulnerability. This report reviews several sources of individual variability, particularly as they relate to differential impairment effects. These sources, which include such factors as acute peak effects, acute tolerance, chronic tolerance, benzodiazepine receptor affinity and individual sensitivity, need to be examined before quantification of DPL is introduced as a criterion for driving under the influence. Behavioral testing itself may become the critical means of assessing drug- and/or drug with alcohol-induced driving impairment if acceptable standardized procedures can be developed. Attention is drawn to the rapid onset of impairment associated with acute effects of more lipid soluble drugs. The discussion of impairment of benzodiazepines should be seen in the perspective of their relative overall safety compared to other drugs used as minor tranquilizers.
The origin of driving accidents is polyfactorial. If the mediocrity of the road network, the technical failures of the vehicles, the violation of the highway code represent an important percentage in the cause of accidents, the great purveyor remains "drunk driving" in the global number of accidents as well as in their importance. The public authorities have not only established laws in this matter so as to penalize alcohol consumption, but furthermore, have initiated a wide programme of verbal information (radio - television), written information (brochures) and iconographic information (posters) to sensitise public opinion on the risks of driving under the influence of alcohol.
The relationship between sensation seeking and risky behaviour has been observed since the 1970s. During the late 1980s and early 1990s, road safety researchers have examined the relationship between sensation seeking and risky driving (e.g. driving while impaired, speeding, following too closely), as well as its consequences (e.g. collisions, violations). There is also growing evidence that sensation seeking may also moderate the manner in which drivers respond to other factors such as alcohol impairment and perceived risk. This paper reviews and synthesizes the literature on sensation seeking as a direct influencer of risky driving and its consequences and as a moderator of the influence of other factors. The vast majority of the 40 studies reviewed showed positive relationships between sensation seeking (SS) and risky driving, with correlations in the 0.30-0.40 range, depending on gender and the measure of risky driving and SS employed. Of those studies that have looked at the subscales of Zuckerman's Sensation Seeking Scale, Thrill and Adventure Seeking appears to have the strongest relationship to risky driving. The biological bases of SS is discussed as are the implications for collision prevention measures.